Thousands of supporters of the president of the United States, Donald Trump, marched through downtown Washington on Saturday, in coherence with his unsubstantiated claims of election fraud.

The protesters carried flags, chanted "stop the steal", and walked from Freedom Plaza near the White House to the US Supreme Court building.

Trump's motorcade briefly drove through the crowds on the way to his golf course in Sterling, Virginia. Demonstrators cheered as the president, wearing a red baseball cap emblazoned with the slogan, waved from inside the presidential limousine.

Biden won 306 votes to Trump's 232 in the state-by-state Electoral College system that determines the winner, which is far more than the 270 required to win the election.

Trump notably has refused to accept the outcome of the US election, even a week after Democrat Joe Biden clinched the polls, and has launched a flurry of dubious legal challenges to overturn the results. The Trump campaign has filed lawsuits in multiple states with little success thus far. Legal experts have said the litigation is extremely unlikely to alter the election outcome.